Field of the Invention
The present invention relates to electro-optical display devices. As examples of electro-optical display devices, there are flat-panel display devices represented by liquid crystal display devices, plasma display devices, organic Electro Luminescence (EL) display devices, field emission display devices, for example. Further, as other examples of electro-optical display devices, there are touch panel display devices including touch panels provided in flat-panel display devices as described above.
Description of the Background Art
Recently, among electro-optical display devices which have been used in a wide variety of applications, for example, liquid crystal display devices have been used in various environments and, particularly, have been increasingly used in corrosive gas atmospheres. Such liquid crystal display devices include display panels incorporating electrodes and various electronic components, and there have been concerns raised about degradation of the functions of these electrodes and these electronic components due to corrosive gasses.
As countermeasures against the aforementioned problem, conventionally, there have been disclosed techniques for protecting electrodes and electronic components provided on display panels through resins applied to the surfaces of the electrodes and the electronic components (refer to Japanese Patent Application Laid-Open No. 10-54992(1998), for example). Further, there have been disclosed techniques for attaching reinforcement plates and the like to electrodes and electronic components provided in display panels for forming protective layers (refer to Japanese Patent Application Laid-Open No. 2007-281378, for example).
In Japanese Patent Application Laid-Open No. 10-54992(1998), a polarization plate is provided in such a way as to protrude from a substrate and, between the polarization plate and the substrate, a resin is embedded on the surface of a terminal of an electrode on the substrate and on the surface of the portion connecting the terminal of the electrode on the substrate to a flexible substrate printed substrate, in order to protect the terminal of the electrode on the substrate and the portion connecting the terminal of the electrode on the substrate to the flexible substrate printed substrate (refer to FIG. 1 in Japanese Patent Application Laid-Open No. 10-54992(1998), for example). However, the resin cannot be sufficiently embedded on an electrode formed on the flexible printed substrate protruded from the embedded-resin portion, particularly on the connection portion thereon, which makes it impossible to completely prevent intrusion of corrosive gas through the cut surfaces of the flexible printed substrate, which are the side surfaces thereof. This has induced the problem of corrosion of the electrode on the flexible substrate due to corrosive gas, thereby inducing the problem of degradation of the quality of the display.
In Japanese Patent Application Laid-Open No. 2007-281378, a reinforcement copper foil as a reinforcement plate is provided on a flexible wiring substrate (see FIG. 1 in Japanese Patent Application Laid-Open No. 2007-281378, for example). However, Japanese Patent Application Laid-Open No. 2007-281378 aims at preventing breakage of wiring of an electrode on the flexible wiring substrate due to mechanical stresses, and cannot prevent intrusion of corrosive gas as described above.